Piler archives lots of data, thus requiring huge disk space. Sometimes it may be better to put these data on an NFS or iSCSI mount. This document describes such a configuration.
In the following example we put the store directory to an NFS mount, everything else remains on the email archiving host:
/var/piler/store ==> NFS server
Steps on the NFS server
#1 Create the piler group and user with the very same gid and uid as on the archiving host:
groupadd -g 1234 piler
useradd -g piler -u 1234 .... piler
#2 Add the following share on the NFS server (/etc/exports)
#3 Reload the exports:
#4 Create the top level store direcory on the NFS share:
chown piler:piler /data/00
Steps on the archiving host
#5 Stop piler on the archiving host, and make sure there’s nothing in the store directory:
rm -rf /var/piler/store/*
#6 Mount the NFS share on the archiving host:
mount nfs-server.yourdomain.com:/data /var/piler/store -o soft,timeo=10,retrans=3,vers=3,proto=tcp
Or you may put it to /etc/fstab:
nfs-server.yourdomain.com:/data /var/piler/store nfs soft,vers=3,timeo=10,retrans=3 0 2
#7 Finally start piler:
It’s important to tune the timeo and retrans parameters that
timeo * retrans < mail server's timeout value
to handle the outage of the NFS server properly. retrans=3 and timeo=10 give the NFS server a ~30-35 second window until piler declares a failure, and returns a 451 error code to the mail server. So it’s important that the mail server mustn’t give up before piler has the chance to respond with a proper error code.
Also make sure to monitor the availability of the NFS share.